Mining-tool.



PATENTBD JULY 21,1908.

M. B. THOMAS.

MINING TOOL.

APPLICATION FILED MAR.17.1908.

. ammi? attorney:

i more especiall UNITED- STATES PATENT OFFICE.

MAUDIE E. THOMAS, or OTTUMWA, IOWA, ASSIGNOR or ONE-HALF TO WILLIAM H. c. nouns,

or OTTUMWA, IOWA.

MINING-TOOL.

Specification ofLe tters Patent.

Patented July 21, 1908.

Application filed. March 17, Serial No. 421,702.

tumwa, in the county of Wapello and State of Iowa, have invented a new and useful Mining-Tool, of which the following is a specifica-. tion.

This invention relates to a mining tool, to one adapted for mining coal; and has or its object to provide a tool preferably w th a twisted shank resembling an auger, the cutting edges of which consist of rotatable disks pivotally mounted on the lower end of the twisted shank,'each with its cutting edge in a plane inclined rearwardly and upwardly from a plane tangent to the lowest point of each cutting edge. The cutting edges of the disks project. below the lower end of the shank and slightly beyond its periphery so that the hole cut thereby will be a little larger-than the body of the tool.

Another object of the invention is to provide a simple means for mounting the cutting disks on the shank so that they can be quickly removed when dulled and sharp ones substituted.

With these and other objects in view the invention consists of the novel combination, construction and arrangement'of arts hereinafter described and claimed, re erence be-- ing had to the accompanying drawings forming a part of this specification, in which Figure 1' is an elevationof the cutting end of the improved mining tool; Fig. 2 an elevation of the tool at a rig t angle to Figi. 1; Fig.

' view of a inodified form of support'or bearing for a cutting disk.

Similar numerals of reference are used for the same parts in all the figures.

The twisted shank 1 of the tool'has its lower end 2 slightly eonvexed, the corners 3, thereof, being curved as shown. A bearing plate 4, of iron or steel, shaped at its upper end to correspond to the curvature of the shank l and extending across the center thereof, is secured on each of its faces at op-' posite sides of the axis thereof by rivets 5,

said rivets passing through both plates and the twisted shank 1. The lower end of each late 4 is offset to produce a space 6 between itself and the shank 1 to receive a cutting disk 7 rotatably mounted on a pivot bolt or pin 8 the ends of which are carried respectively by the shank and the bearing plate. This construction produces an exceedingly simple and efficient boring tool, there being no wear. on any part except the cuttingdisks .which may be, quickly renewed as soon as they become dull by removing their pivot bolts or pins and substituting new cutters which may be accomplished very quickly and without any appreciable loss of time and at slight expense. I

It is to be noted that the pivots of the cut ting disks are seated at one of their ends in the shank itself and at their other ends in a plate strongly riveted to the auger. The cutting disks have thus a firm, rigid and simple bearing, easily and cheaply made and quite compact. The cutting disks have theirpivots disposed at such an angle that said disks incline u wardly from the cutting plane and rearwar y with respect to the direction of movement of the tool when in use.

As thus disposed, the cutting disks when pressed against the material to be cut, are caused to rotate by frictional contact and rapidly disintegrate the material and bore a smooth cylindrical hole therein. The cutting disks are each preferably formed with a sharp cutting eriphery thickened at the center for the ho e through which the pivot pin passes, resembling two shallow cones united at their bases, their apices forming the hub. Amodified form of bearing for the cutting disk is illustrated in Fig. 4 and consists of a casting or forging 10 havingan u wardly extendinglu 11 shaped on one si e to fit the spiral shank 1 and provided with one or more erforations for fastening rivets or bolts. oining this lug 11 is a lip 12 between which two parts is a notch 13 for thelower end of.

the tool shank. The lower art of the bearing 10 is slotted upwardly om the bottom end to receive the cutting disk 7 pivoted on a pin 8 passing through the lower ends of the gers 13 and 14 produced by the slot 15.

claimas new and desire to secure by Letters Patent is:-- i o 1. A mining tool comprising a shank and rotatable cutting disks mounted therein with their axes inclined to the cutting plane;

2. A mining tool comprising a shank and rotatable cutting disks: mounted on the end thereof with their cutting edges each in a plane inclined upwardly and rearwardly from a common plane tangent to the lowest point ofeach cutting edge.

3. A mining tool comprising a twisted shank, and cutting disks on the end thereof, one of said disks being rotatably mounted on each face of said shank in an inclined position their cutting edges projecting in advance of the shank.

4. A miningtool comprising a shank, cut-' the shank and projecting beyond the same, and pivots for said disks seated at their ends in the shank and the bearing plates and inclined to the cutting planeof said disks.

5. A mining tool com rising a twisted shan'k, cutting disks on t e end thereof a bearing late riveted. to each face of said twisted s ank and secured thereto by rivets or bolts common to both bearing lates, said 'bearing plates spaced at their ower ends from the shank to receive said cutting disks, and removable ivots for said disks seated in the shank an the bearing plates.

In testimony that I claim the foregoing as my own, I have hereto aflixed my signature in the presence of two witnesses.

MAUDIE E. THOMAS. 

